JPS643309B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for manufacturing a fluorescent display tube.

Fluorescent display tubes produce light-emitting displays by causing electrons emitted from a heated filament-shaped cathode to collide with an anode that has a phosphor layer applied to its upper surface.The fluorescent display tube has a good luminescent color and can be driven at a low voltage. It has advantages such as low power consumption and is widely used as a variety of display units.

Particularly recently, it has been widely used as a display part for not only calculators and watches, but also home appliances, automobiles, audio, measuring instruments, etc., and with the expansion of these uses and the diversification of display designs, a wide variety of products and small quantities are being produced. There is a trend of increasing production.

However, when changing the display size or display design, it is necessary to not only change the shape of the anode and phosphor layer, but also the size and shape of the lead frame that makes up the leads for leading the internal wiring to the outside. need to be changed. Since the anode and phosphor layer are formed by printing, it is relatively easy to change the shape, but the lead frame is generally made by press shearing, and unnecessary parts are removed after being sealed to the envelope. Cutting and removing
It is necessary to create a dedicated press mold for each product type, and it is also necessary to prepare a variety of peripheral jigs for each product type, such as welding jigs, intermediate processing molds, and assembly processing jigs. , and preparations for machining these peripheral jigs require a longer preparation period and more material is wasted. Therefore, there was a problem that not only an increase in manufacturing costs was unavoidable, but also a decrease in production efficiency.

The present invention has been made in view of the above points, and it provides an internal wiring that is connected to the lead portion even if the number of leads changes when the size or design of the fluorescent display tube changes. Focusing on the fact that the terminals of the 2000 can be formed with a predetermined pitch or a pitch that is an integral multiple of the predetermined pitch, and also paying attention to the fact that the length of the leads does not change, we separated the long lead frame material and the cathode holding member. A long lead frame material is cut into a length according to the size of the fluorescent display tube, and a cathode holding member is attached to this to use as the lead frame part. It is now possible to use a common lead frame for fluorescent display tubes with different designs, which improves material yield, and especially because there is no need to form a dedicated mold for each display tube. It is an object of the present invention to provide a method for manufacturing a fluorescent display tube that can improve production efficiency and reduce costs.

Next, the present invention will be described with reference to an illustrated embodiment. 1A, B, and C are explanatory diagrams showing the manufacturing procedure of a lead frame part using a lead frame material and a cathode holding member, and 1 in the figure is a band-shaped glass having thermal expansion characteristics equivalent to those of glass. Fe is a metal material for sealing and is usually called 426 alloy.
-Ni-Cr alloy etc. are used. This metal material for glass sealing is cut, for example, by a roller cutter 2 having blades that alternately change the U-shaped direction and punch out continuous zigzag shapes, so that two long lead frame materials 3, 3 are continuously formed at the same time. be done.

Here, an example is shown in which a set of roller cutters 2 is used to simultaneously form two lead frame materials 3, 3. Two sets of roller cutters, one for punching out the lead 4 continuously in a stepwise manner and another for cutting out the gap 42 at the tip of the lead 4 alternately, or one pitch or a plurality of roller cutters may be used, regardless of the roller cutter. Punch out each pitch in a progressive manner 1
Of course, by using a press using a seed or two types of press cutting dies, etc., it is possible to continuously form the lead frame materials 3, 3 having the above-mentioned opposing comb-like lead portions 4. be.

In this way, each lead frame material 3, 3 is continuously formed with comb-like lead portions 4 at the same pitch in opposing directions, and each lead frame material 3, 3 is wound onto a reel 5, and the Prepared when assembling to the frame part 6.

The pitch of this lead portion 4 is set to be the same pitch as a terminal portion of internal wiring, which will be described later, or to one integer fraction of the pitch of this terminal portion.

When in use, the long lead frame material 3 wound on the reel 5 is pulled out and cut to an appropriate length depending on the size of the fluorescent display tube to be used, and a separately prepared material is attached to each end of the lead frame material 3. The cathode holding members 7, 7 are welded parallel to the lead portion 4 to form a substantially U-shaped lead frame portion 6.

Further, if necessary, an auxiliary member 8 is provided between the other ends of the cathode holding members 7 and 7 and fixed by welding or the like.
The entire frame may be shaped like a rectangle. Since this auxiliary member 8 is removed in the final process, there is no need to use expensive sealing metal materials such as the lead frame material 3 and cathode holding members 7, 7, and instead it is made using inexpensive iron, iron-nickel alloy, or stainless steel alloy. etc. can be used. Further, the cathode holding member 7,
A filament cathode 9 is stretched between the filament mounting members 7a and 7a.

On the other hand, as shown in the exploded perspective view of FIG. 2, a wiring conductor 11, an insulating layer 12, a segment anode conductor 13, and a phosphor layer 14 are sequentially stacked on a glass substrate 10 to form an anode substrate 15. , its insulating layer 12
A terminal portion 16 is provided in a portion of which the wiring conductor 11 is exposed.

The terminal portions 16 are provided at the same pitch as the lead portion 4, or an integral multiple thereof, or a combination of the same pitch and an integral multiple thereof.

In addition, a box-shaped front envelope 17 constituting an envelope together with this anode substrate 15 is attached to a side plate 17a and an upper plate 17b made of glass whose top surface is transparent at least.
An exhaust pipe is formed in a part of this side plate 17a to communicate with the inside thereof.

Next, the lead frame portion 6 is placed on the anode substrate 15, and the lead portion 4 and the terminal portion 16 of the wiring conductor 11 are connected by contacting or bonding with a conductive adhesive as necessary. In this case, one lead part 4 of the lead frame part 6 is connected to one terminal part 1.
6, the lead portion 4 will automatically fit onto the remaining terminal portion 16, making it extremely easy to align the two. Further, the anode substrate 15 and the front enclosure 17 are attached to the lead frame portion 6 so as to enclose the central portion of the lead frame portion 6.
A part of the glass is sandwiched and sealed with low melting point fritted glass or the like.

By the way, when the terminal portions 16 and the lead portions 4 are arranged at the same pitch, the lead portions 4 and the terminal portions 16 correspond one-to-one, but if the terminal portions 16 are missing, the excess lead portions 4 occurs. This extra lead portion 4 may be left as is or may be cut and removed before the lead frame portion 6 is placed on the anode substrate 15.

As shown in FIG. 3, the lead portion 4 and the cathode holding member 7 are sandwiched and fixed by the anode substrate 15 and the front enclosure 17, and are securely fixed.

Next, as shown in FIG.
By cutting and removing unnecessary parts of the auxiliary member 8 and the auxiliary member 8, the fluorescent display tube D is completed, and the lead portion 4 and the cathode holding member 7, which are led out from the envelope, are connected to various electronic or electrical sources. It is connected to a device drive circuit (not shown).

By the method described above, the lead frame material 3 can be used in common even for fluorescent display tubes of different sizes or designs.
In addition, since two lead frame materials 3 are made simultaneously and continuously from the band-shaped sealing metal material 1, it is excellent in mass production, and there is very little waste of expensive sealing metal materials, resulting in material savings. It will be possible to achieve this.

5A, B, and C show other embodiments of the lead frame material 3 used in the present invention, and FIG. An example is shown in which a plurality of holes 20 are formed at pitch intervals corresponding to the pitch intervals of the lead part 4, and the lead frame part 6 is connected to the anode substrate 1.
If a positioning protrusion that fits into the positioning hole 20 is formed on the support jig (not shown) used when attaching the lead frame section 6 to the anode substrate 15, the attachment of the lead frame section 6 to the anode substrate 15 will be accurate and speedy. It will be possible to do so.

FIG. 5B shows a dividing groove 21 at the tip 4a of the lead part 4.
Fig. 5C shows an example in which the tip 4a of the lead portion 4 is made thinner to improve contact with the wiring conductor 11 in the same way as Fig. 5B. It shows.

FIG. 6 shows a cathode holding member 7 used in the present invention.
This shows another embodiment, in which a slit 22 is formed in a part of this cathode holding member 7 along the longitudinal direction, and one side separated by this slit 22 has a width equivalent to that of the lead part 4. The cathode lead 7b has one side, and the other side has a reinforcing piece 7c. Furthermore, a notch 22a is formed on the base side of the reinforcing piece 7c to facilitate cutting.

This cathode holding member 7 is fixed to the lead member 3 with the same pitch as the pitch between the adjacent lead parts 4. Furthermore, in the above embodiment, an example is described in which the present invention is applied to a fluorescent display tube with a diode structure consisting of a filament cathode 9 and an anode part, but it can also be applied to a fluorescent display tube with a triode structure having a control electrode.
The present invention can be applied as long as the terminal portions of the control electrode and the terminal portions of the internal wiring conductor that connect the control electrode and the lead portion are arranged at a predetermined pitch or an integral multiple of the predetermined pitch. Needless to say.

Here, in the embodiment of the present invention described above, the lead frame material 3 is cut into a predetermined length, and the cathode holding members 7, 7 are welded to both ends to form the lead frame portion 6. An example has been shown in which a band plate-shaped auxiliary member 8 is fixed between the other ends of the members 7 and 7 to form a rectangular frame as a whole. However, the present invention is not limited to this, and for example, in the case where the leads 4 are extended not only below the anode substrate 15 but also above the anode substrate 15,
Of course, the lead frame material 3 can be used as the auxiliary member 8.

In addition, the present invention is not limited to the embodiments described above and shown in the drawings, but can be implemented with various modifications without changing the gist thereof.

As explained above, according to the present invention, when forming the lead frame part, the lead frame material and the cathode holding member are formed separately, and the long lead frame material is made to fit the size of the fluorescent display tube. Since the lead frame material is cut to a suitable length for use, the lead frame material can be used in common even for fluorescent display tubes of different sizes or designs. Therefore, even if there is a change in size or design, there is no need to manufacture a mold each time, and peripheral jigs for welding etc. can be used as they are, reducing production efficiency and manufacturing costs associated with high-mix, low-volume production. This has the effect of avoiding cost increases.

In addition, in the present invention, if a part of the cathode holding member is made to have the same shape as the lead part and this cathode holding member is attached at a position with the same pitch interval as the lead part, the lead part and the external drive circuit can be connected. This has the effect of making it easier to connect, for example, allowing common use of connectors and the like.

Furthermore, in the present invention, if one strip of metal material is cut into a zigzag pattern and two long lead frame materials are simultaneously and continuously formed, expensive sealing metal materials can be wasted. The number of parts that need to be removed is extremely reduced, which results in the effect of saving materials and reducing costs by improving mass productivity.

[Brief explanation of drawings]

The drawings are diagrams illustrating an embodiment of the method for manufacturing a fluorescent display tube of the present invention, and FIGS. 1A, B, and C show the steps for manufacturing a lead frame portion using a lead frame material and a cathode holding member. Explanatory drawings, Fig. 2 is a perspective view showing the process of sealing the front envelope together with the electrode assembly frame to the anode substrate, Fig. 3 is a front view of the same, and Fig. 4 shows cutting off unnecessary parts of the lead frame part. Explanatory drawings showing the process; FIGS. 5A, B, and C are front views of main parts showing other embodiments of the lead frame material; FIG. 6 is front views of main parts showing other embodiments of the cathode holding member. . DESCRIPTION OF SYMBOLS 1... Band-shaped metal material for glass sealing, 3... Lead frame material, 4... Lead part, 6... Lead frame part, 7... Cathode holding member, 8... Auxiliary member, 11... Wiring conductor, 12...Insulating layer, 13...
...anode conductor, 14...phosphor layer, 15...anode substrate, 17...front envelope.

Claims (1)

[Claims] 1. A manufacturing process for an anode substrate in which a wiring conductor, an insulating layer, an anode conductor, and a phosphor layer are laminated on a substrate, and a long process in which comb-like lead portions are formed at a predetermined pitch. A step of manufacturing a lead frame material, cutting the lead frame material into a length corresponding to the size of the anode substrate, and adding the following steps to both ends of the lead frame material:
A step of fixing a cathode holding member formed separately from this lead frame material to form a lead frame part, and fixing the other end of the cathode holding member fixed to both ends of the lead frame part with an auxiliary member. and a step of arranging a filament cathode in a stretched manner between the cathode holding members, and a part of the lead frame portion is held between the front envelope and the anode substrate, which constitute an envelope together with the anode substrate. A method for manufacturing a fluorescent display tube, comprising the steps of: sealing the front envelope to an anode substrate; and removing an unnecessary portion of the lead frame. 2. At least one end of the cathode holding member has the same shape as the lead part of the lead frame material, and the cathode holding member has a pitch interval of the lead part on the outside of the lead part located at both ends of the lead member. A method of manufacturing a fluorescent display tube according to claim 1, wherein the fluorescent display tubes are fixed at equal intervals. 3. The step of manufacturing the long lead frame material involves cutting a single band-shaped metal material into zigzag shapes using a combination of comb-tooth-shaped materials.
2. A method for manufacturing a fluorescent display tube according to claim 1, wherein two sheets of lead frame material are formed at the same time.